AIR links between Hongkong, Taiwan and China will be discussed in a conference to be held in Taipei in November, according to a Taiwan scholar involved in the preparation of the event. Professor Cheng Chia-jui of the Graduate School of Law of the Soochow University in Taiwan said yesterday aviation experts and international law specialists from the three sides would attempt to sort out the myriad of legal questions surrounding the issues at the conference. While preparations were still under way, he said it was expected that an international law expert from the Hongkong University and representatives from Cathay Pacific Airways and the Hongkong Government would be invited. Top representatives from the six major mainland airlines and legal experts from Beijing are also on the invitation list. According to Professor Cheng, Hongkong's status as an international air transport centre will be in doubt unless the legal implications are resolved. In Hongkong attending a legal seminar, Professor Cheng said both the Joint Declaration and the Basic Law provided little details on Hongkong's position as an aviation centre. He felt that drafters of the Basic Law and the Joint Declaration had failed to take into account the possible consequences of the two documents on areas such as aviation and transport. In a paper to be delivered in the seminar today, Professor Cheng said the future Hongkong-Taipei service might be considered a ''domestic flight'' under the Chicago Convention - an international air traffic agreement of which both China and Britain are contracting parties, but not Taiwan. Under the convention, air traffic between Hongkong and other Chinese cities will become a ''Chinese cabotage route'', meaning that Beijing will have exclusive right to determine the operation of these routes. ''Should BA (British Airways) be allowed to carry the passengers from Hongkong to . . . China after 1997? The answer will be negative because it is contrary to the principle of cabotage formulated by customary rule of international air law,'' Professor Cheng said. He said while the Hongkong Special Administrative Region was authorised by the Joint Declaration to independently negotiate aviation agreements with third countries, Taiwan was apparently not included under such provision. ''Therefore, the Hongkong-Taipei service is theoretically and politically not international. Nonetheless, Taiwan is not ready, at present, to accept that the Hongkong-Taipei service is domestic because recognition of domestic routing is equal to recognising the Central Government of the People's Republic of China,'' he said. ''In short, the freedom identity of the Hongkong-Taipei route is essentially [a] political question, the solution of which lies beyond a literal interpretation of the Chicago Convention and the Basic Law.'' Another pertinent issue will be the question of whether to allow all carriers registered in the Hongkong SAR to fly to any points of destination in China. According to Professor Cheng, any airlines which can prove a ''real and effective link'' with Hongkong will be eligible to apply for permission to offer air services between Hongkong and the mainland after 1997.